This invention pertains to actuators for moving storage devices and more particularly to a magnet assembly for voice coil motor driven actuators for such devices.
Higher performance is continuously demanded of rigid magnetic disk drive actuators for quicker access, which requires stronger flux fields to increase the drive of the voice coil motor. This can be accomplished by a high continuous, uninterrupted high permeability flux path from one side of the working gap to the other, and strong permanent magnets. Not only are larger or stronger magnets required, but also form factor limitations imposed by standard overall dimensions that limit the space available and demand a compact structure must be accommodated.
Stronger fields make shielding even more important to keep stray fields from the disk surface areas or locations where interference with other components may occur. Stronger permanent magnetic materials makes progressively more difficult the fabrication technologies that require a magnet and core to be axially assembled with minimum or zero clearance therebetween.